"P" is for Physics
X-rays, CT, and nuclear medicine all use this type of particle to create images
Photon
In most imaging modalities, this is what happens to resolution when the signal is increased
It decreases
These are the main units of dose used in medical imaging
mGy and mSv (Gy = J/kg)
This is the source of contrast in x-ray and CT imaging
Attenuation
DECT
Dual Energy Computed Tomography (uses two different kVps to get additional image contrast)
The reason that contrast improves when reducing kVp is the increase of this type of particle interaction
Photoelectric
This type of filter after reconstruction can help increase the resolution of an image
High-pass
The dose from a CT scan can be decreased most directly by decreasing these two factors
kVp and mAs
This is what the "E" stands for in PET
Emission
DRR
Digitally reconstructed radiograph ("fake" planar x-ray constructed from planning CT)
This is what the "P" in PET stands for
Positron
For a given number of phase and frequency encodings, increasing this parameter will worsen the resolution of an MRI image
Field of View (FOV)
This is the acronym used for avoiding unnecessary radiation exposure
ALARA
This word is used to describe the behavior of hydrogen nuclei (protons) in a magnetic field
Precess
EPID
Electronic portal imaging device (uses MV beam, lower contrast than keV x-rays)
Helical CT scans have this additional parameter that does not apply to axial CT scans
Pitch
Increasing the number of gray levels in an image can improve this type of resolution
Contrast resolution
These two imaging modalities deliver no ionizing radiation dose to patients
MRI and Ultrasound
This is a leading cause of contrast reduction in imaging with photons
Scatter
DICOM
Digital Imaging and Communications in Medicine
This type of material is used in the transducers employed in Ultrasound imaging
Piezoelectric
This x-ray imaging detector provides the best image resolution
Film
Skin redness and vomiting are two examples of this type of dose effect
Deterministic
This is the main physics phenomenon contributing to the x-ray spectrum from an X-ray tube
Bremsstrahlung (higher Z material in target, more photons)
QC
Quality Control (essential for all imaging devices, typically daily, weekly, monthly, quarterly and annual checks)